The invention relates to a pump unit which is to be arranged in a surge chamber of a fuel tank of a motor vehicle, having a fuel pump which is provided for pumping fuel to an internal combustion engine of the motor vehicle, having an ejector pump which is connected to the fuel pump and is used to pump fuel out of the fuel tank into the surge chamber, and having at least one filter element for filtering fuel, a housing part which is connected to the fuel pump having at least one channel which is provided for guiding the fuel.
Pump units of this type are frequently used in motor vehicles today and are known from practice. The housing part of the known pump unit has a flange with which it is inserted into a recess of the surge chamber and is sealed with respect to the latter. The channel leading to the intake side of the ejector pump is guided as far as the flange. The filter element is fastened on the lower side of the surge chamber and has an edge with which it is sealed with respect to the surge chamber.
A disadvantage of the known pump unit is that it is of very complex construction and pre-assembly to form individual subassemblies which can be combined with one another is not possible.
The invention is based on the problem of designing a pump unit of the type mentioned at the beginning in such a manner that it is of particularly simple construction and enables substantial pre-assembly.